Roller supports for rotary kilns, e.g., British Patent Specification No. 1,527,419, are known in which the weigh beam can rock on its rocking bearing thus making it possible for the axis of the roller to always adjust itself automatically in accordance with the inclination of the axis of the live ring and consequently of the kiln. This ensures a complete line contact between the live ring and the roller support at all times, and thus minimal Hertz-stress between these parts.
However, it is known that the drums and especially rotary kilns undergo appreciable heat expansion in the axial direction. Because of this expansion at any rate, some of the live rings secured to the drum change their position in the axial direction in relation to the rollers of their roller supports since the rollers are normally incapable of a similar axial displacement. In the case of the above known support, the rollers are actually retained in position so as to avoid displacement. This is made possible by suspending their weigh beam in rocker arms which permit no such displacement. If the live ring is displaced in the axial direction it will thus only be in line contact with a certain part of each roller, which involves an unequal load on the latter as well as on the bearings thereof. If the rollers have not been constructed so as to be broader than the live ring, which in the event of axial displacement does not project beyond its rollers, there may further be an undesiredly large Hertz-stress between the roller and the live ring. I have eliminated the above-noted disadvantages of the known roller support.